关键词: 振动与波, 冲击, 推进轴系, 舰船, 转子

Abstract: The anti-shock performance of the propulsion shafting is one of the decisive factors for the survival of warships. In this paper, the rotating propulsion shafting is treated as a low-speed rotor dynamic system. Based on the rotor dynamics theory, a finite element model of the rotating propulsion shafting is developed for analyzing its dynamic response under shock load. The differential equation of the presented model is solved by using the Newmark method. The characteristic of the dynamic response of the propulsion shafting under lateral shock load and the effects of rotation speed on the response is investigated through numerical simulations. It is found that the gyroscopic effect of the rotating shafting makes the bending vibrations in horizontal and vertical direction coupled, and the gyroscopic effect can be equivalent to a system’s damping effect. It is found that when the damping of shafting is smaller, the gyroscopic effect on the dynamic response is relatively larger. The maximum shafting deflection under lateral shock occurs at the middle of a segment of the shaft between two neighbouring bearings with larger spacing. Since the bending deflection of the shaft can absorb the shock energy effectively, the acceleration of propeller is greatly attenuated.

Key words: vibration and wave, shock, propulsion shafting, warship, rotor